Background of VL Myrsky
1933 Finnish Air Force has only seven flying squadrons including only one fighter squadron (LLv 24) equipped by Gloster Gamecock II fighters. The second fighter squadron (LLv 26) established late 1933 and equipped by Bristol Bulldog IV fighters next year.
Finland committed to Bristol aero engines
FAF has decided to choose Bristol Jupiter to the main engine of war planes around 1925. Unfortunately, FAF had to purchase engines from Gnome & Rhone according to the licence agreement between Bristol and Gnome & Rhone. The engines were proved to unreliable.
1935 Finland managed to make a licence agreement between Tampella and Bristol according to Bristol Mercury and Bristol Pegasus aero engines. Tampella started the production of Mercury and Pegasus and FAF was committed to purchase them from Tampella.
Replacement of Gloster Gamecocks and Bristol Bulldogs
Same year FAF started the process to purchase a fighter to replace old Gamecocks of LLv 24. In all 26 call of tenders have been sent and seven tenders have been received: Dewoitine 510, Fokker D.XXI, Gloster Gladiator, Morane-Saulnier M.S.405, North American NA-16-15, PZL P.24 and Vought V-143. Others but Fokker and PZL falled off due to either performance, armament or price. Fokker D.XXI was chosen due to long proved commercial relationships, the Bristol Mercury aero engine and construction which was compatible with the production of State Aircraft Factory.
September 23rd 1936 Defence Council decided to order seven Fokker D.XXI fighters and licence to build 14 aircraft in Finland. Next year Finland decided to replace Bulldogs with Fokker D.XXI. licence transferred to unlimited and FAF ordered 21 additional Fokker D.XXI fighters from State Aircraft Factory. Seven D.XXIs have been delivered during the summer 1937 and State Aircraft Factory delivered 35 aircraft between November 1938 and July 1939.
More fighters are needed...
Marshall Mannerheim (as the chairman of Defence Council) advanced September 26th 1938 the opinion that Finland should purchase aircraft from abroad in order to prepare to coming war. FAF started a procurement process without permission to buy any aircraft since the allocations have been used to 42 Fokker D.XXIs to two squadrons. During April 1939 FAF proposed to replace fourth bomber squadron with third fighter squadron according to experiences from the Spanish Civil War.
May 26th 1939 commander of FAF, General Lundqvist introduced a list including over 20 possible and impossible alternative fighters. For example, Curtiss Hawk 75A, Fiat G.50, Fokker D.XXI and Morane-Saulnier M.S.406 did not fulfil the requirements of the specification. Hawker Hurricane, Heinkel He 112, Messerschmitt Bf 109, Seversky EP-1, Supermarine Spitfire and all five alternatives of State Aircraft Factory were acceptable from the technical point of view.
Design of VL Myrsky ordered
General Lundqvist proposed a domestic fighter (later VL Myrsky) for the new fighter squadron (LLv 28) but his proposal has not been accepted. FAF ordered only the design work of VL Myrsky from State Aircraft Factory but not the prototype. However, the planned Bristol Taurus engine had to be changed to Pratt & Whitney R-1830 S3C3-G Twin Wasp due to the British embargo on war materials.
Domestic fighter production was a objective itself since the fighter deliveries from abroad were regarded as unreliable and expensive. Another reason was internal politics: domestic aircraft production supports employment.
FAF ordered Fiat G.50s as an expedient
The outbreak of the war in Poland at the beginning of September 1939 led to expedients. Finland bought 25 Fiat G.50s (and later 10 more) from Italy to LLv 28 due to rapid delivery. Furthermore, FAF ordered 50 Fokker D.XXI fighters from State Aircraft Factory. Since the Bristol Mercury engines were reserved to Bristol Blenheims, new Fokkers adjusted to Pratt & Whtiney R-1535 Twin Wasp Junior engine.
The outbreak of the Winter War halted the design work of VL Myrsky and the State Aircraft Factory focused on repair work of war planes.
Fighter purchases during the Winter War
By using all possible diplomatic and other relationships, Finland managed to buy 20 Gloster Gladiator II and 12 Hawker Hurricane I fighters from U.K. and 44 Brewster 239 fighters from the USA. Furthermore, France donated 30 Morane-Saulnier M.S.406 and 6 Caudron C.714 fighters and U.K. 10 Gloster Gladiators and 24 Gloster Gauntlets. Caudrons and Gauntlets (as well as Bulldogs and Jaktfalkens donated by Sweden) were obsolete. However, the fighter inventory after the Winter War was better than before it.
Gamecocks claimed one, Bulldogs six, Fokker D.XXIs 127, Fiat G-50s 11, Morane-Saulniers 14 and Gladiators 34 kills. Hawker Hurricanes and Brewster 239s came too late.
Fighter purchases during Interim Peace
The design work of VL Myrsky continued after the Winter War as an emergency project and FAF ordered one prototype of VL Myrsky December 20th 1940. One Twin Wasp engine and Hamilton Hydromatic propeller ordered and delivered from the USA. Unfortunately, the further engine deliveries were not possible after USA appointed an embargo on war materials July 2nd 1941. Additionally, Finland tried to make licence agreement in order to build Brewster 239 or Seversky EP-1 but without any success.
Germany and Finland agreed about right to transfer German troops via Finnish ports, railways and roads to Norther Norway September 1940 (and Soviet Union get almost same right to transfer troops via railways between Soviet Union and the naval base on Hanko Peninsula at the same time). Germany promised to compensate munitions stopped on German ports during the Winter War by delivering some munition to Finland.
Unfortunately, FAF was allowed to buy only German war booty, including 25 almost obsolete ex-French Morane-Saulnier M.S.406 fighters, 16 ex-French Curtiss Hawk 75A fighters and 13 ex-Norwegian Curtiss Hawk 75A-6 fighters.
State Aircraft Factory delivered 49 Fokker D.XXI between October 1940 and June 1941. These fighters have been equipped by Pratt & Whitney R-1535 Twin Wasp Junior engine. One D.XXI with retractable landing gear delivered next year. Due to less powerful engine and higher take off weight, Fokkers with Twin Wasp Junior engine were rather advaced trainers than first line fighters.
At the end of Interim Peace Finland has five fighter squadrons:
- LLv 24, Brewster 239s
- LLv 26, Fiat G.50
- LLv 28, Morane-Saulnier M.S.406
- LLv 30, Hawker Hurricane and Fokker D.XXI
- LLv 32, Fokker D.XXI (but get Curtiss Hawk 75A soon)
The number of fighters in order June 20th 1941:
- 37 Brewster 239s (+ 5 in service or in repairing at State Aircraft Factory)
- 0 Curtiss Hawk 75A (+ 8)
- 16 Fiat G.50 (+ 16)
- 23 Morane-Saulnier M.S.406 (+16)
- 38 Fokker D.XXI (+ 32)
- 7 Hawker Hurricane (+ 2)
- 17 biplanes (Gladiator and Polikarpov I-153) (+ 14)
So, FAF has only 131 fighters in service (excluding biplanes) June 20th 1941. Brewster 239 was superior to Polikarpov I-153 and I-16 but other were satisfactory or obsolete.
Fighter purchases during Continuation War
Germany did not sell modern fighters at the beginning of Continuation War to Finland. Therefore Finland has to continue the development work of VL Myrsky and started a project to produce Brewster 239s in Finland (VL Humu). However, FAF was allowed to buy 32 absolutely obsolete ex-French Morane-Saulnier M.S.406 and 410 fighters (delivered between August and October 1942) and 15 ex-French Curtiss Hawk 75A fighters (delivered between June 1943 and January 1944).
FAF get information concerning possibility to buy ex-French Pratt & Whitney R-1830 SC3-G Twin Wasp engines at the beginning of the year 1942. During 1942 and 1943 Finland bought 127 Twin Wasps (and Sweden 115) from the war booty storages of Germany. FAF ordered three preproduction aircraft (VL Myrsky I) May 30th 1942 and 47 VL Myrsky II fighters August 18th 1942.
Possibility to get an alternative engine (Mercedes-Benz DB605A) to VL Myrsky led to a parallel project since it was not possible to install V-12 engine in the airframe of VL Myrsky. FAF ordered design work and two prototypes of VL Pyörremyrsky from State Aircraft Factory November 29th 1942. Five preproduction VL Humus were ordered from State Aircraft Factory October 16th 1942 and 200 Shvetsov M-63 engines ordered from German war booty storages during the same month.
The poor war plane situation (in quality and quantity) in fighter squadrons led to the fourth domestic fighter development project during 1942. State Aircraft Factory made an experimental installation of 1 100 hp Klimov M-105 engine to Morane-Saulnier M.S.406 to replace 860 hp Hispano-Suiza. Finland ordered 85 Klimov M-105 engines from the German war booty storages November 23th 1943 and the engines were delivered during February 1944.
After collapse in Stalingrad, German delivered 16 new and 14 repaired Messerschmitt Bf 109 G-2 fighters between March and May 1943. Only one fighter squadron (LLv 34) get Bf 109s and FAF got 18 Bf 109 G-2s to substitute war losses between August 1943 and January 1944.
Three VL Myrsky preproduction aircrafts were delivered during April - July 1943 and used for testing purposes. All preproduction aircrafts destroyed between June 1943 and 1944.
Germany delivered another Messerschmitt Bf 109 squadron after the siege of Leningrad collapsed January 1944. 30 Messerschmitt BF 109G-6 delivered during March and April 1944. LLv 34 got new fighters and delivered older G-2s to LLv 24. The war losses of LLv 34 replaced by additional 18 G-6s during June 1944.
FAF made a program during February 1944 to eguip the fighters of all seven fighter squadron by Messerschmitt Bf 109s. After Vyborg-Petrozavodsk Offensive has started, Germany informed June 16th 1944 that Finland was allowed to by 242 Messerschmitt Bf 109 G fighters (+ 180 spare engines). The third Messersschmitt squadron (30 Messerschmitt Bf 109 G-6s) delivered between June 20th and July 2nd 1944 and after that 29 aircrafts to replace war losses between July 2nd and August 23th 1944. The fourth promised squadron delivered only partly since Germany delivered 10 Messerschmitts before Finland and Soviet Union made peace.
47 VL Myrsky II fighters delivered December 1943 and May 1945.
Originally the VL Myrsky project was not any emergency project. Domestic fighter production has been seen as a way to spare currency, support employment, maintain independence and get better fighters that by purchasing from abroad.
Later VL Myrsky changed to an emergency project. Lack of modern fighters led to continue VL Myrsky project as well as the situation led to three other projects: VL Humu, VL Pyörremyrsky and Morane-Saulnier M.S.406 engine change (so-called Mörkö-Morane or Ghost Morane).
German Messerschmitt Bf 109 deliveries were very unreliable. First squadron delivered after Stalingrad collapse, second after Leningrad collapse, third after the start of Vyborg–Petrozavodsk Offensive and delivery of fourth Messerschmitt squadron started after the realisation of Ryti-Ribbentrop Agreement (a letter from President Ryti to Chancellor Hitler sent June 26th 1944).